Draft roll



E. J. ABBOTT DRAFT ROLL Nov. 21, 1933.

Filed Oct. 15, 1950 Inventor w r I Q? A it Patented Nov. 21, 1933 ourrso srrss Abbott Mmhlne Gompsny,

Wilton, N. Elli, s cor pcroiion oi NlEWHEiIfifllSllllt9 Application @ctolier 15, 193%. Serial No. ds ddlsli '1 Claim.

This invention relates to draft roll inechanisin for textile machines and is oi particular epplicahiliy in textile machines which handle tentile iifcers (for instance unspun sliver), in connection with a drafting or drafting and combing operation performed thereon. Objects oi the invention are to provide a draft roll construction capable oi improved operation and with which the combing or o her fiber-handling mechanism may react on the fibers at a point relatively close to the cite oi the rolls, wherein mutilation oi the endless apron usuellv employed in connection with one of the rolls is avoided, wherein the roll mechanism is enabled to drew the doors uniiorrn manner regardless of the condition wear of the endless apron, and wherein the draft rolls may lie oi small diameter.

{iii objects of the invention, advantages and structural improvements will appear from a consideration of this enplsnetion of e typical inol the invention shown by way of example in the accompanying drawing.

In drawing:

l is a side elevation, partly in section, oi bcrsulld machine for combing unspun fibers and guiding tne fibers onto a winding spool;

is an elevation of ports of the device oi Fig. 1 locking in the direc ion or" the arrows 2-2 1; and

Fig. 3 is edisgremmstic view of driving con nee-lions or" the device.

is e iregnientenl view corresponding to Fig. 2, showing a modified form of lower roll.

The improved drsit roll conslruction of the present invention issi'lown by way of example in.

l as embodied in a roll mechanism between corrugated rolls ii and 12 on its way from s condenser or other sliverhondiing equipment. A pair of opposed draft rolh l3 end is is provided ior the purpose of the sliver The illustrated machine is shown as having coursing means disposed to react on the sliver, and heroin shown at 15 as of a con ventlonel type comprising moving iallers which rise, move generally with the strand of sliver t ard the draft rolls out at a slower rate, descend out of contsct with the sliver, and return to their initial position.

After passing "between the draft rolls is and i l, the conioed sliver passes through a trumpet guide it which may be of the rotary type, and from thence onto a winding spool 18, herein shown as irlctionslly driven by a driving drum l9. Suitable traverse mechanism, not may proprevent its being cut by textile machine operatingon e strand oi sliver which passes to the draft (@l. lo -M5) vide relative back and forth movement of the spool 18 with respect to the trumpet 17.

Referring to Fig. 3, the'rlriving drum 19 may be mounted upon a shaft 20 which is suitably driven and which serves to drive the lower draft roll is through suitable searing diagrammatically indicated at 21.

The upper "draft roll is shown as mounted on an elevated ireme sui' slclv secured to the ma.- chine ond carrying generally vertical guide rods 25 on which housings 2'! lor the roll are adopted to slide. Pressureineans is provided ior loading the upper roll, causing it to beer heavily upon. the sliver, this pressure means being preferably constituted, as shown, oi strong springs 28, beering at their lower ends against the housings 2? and at \heir upper ends against adjusting nuts so.

The upper draft roll 13 is preferably embraced by an endless apron 23, or leather or other suitable somewhat resilient material which turns with the roll and is adapted to cushion the sliver and the rolls, such apron losing a well known and usual element in devices or this type. This apron runs beneath roll 13, and upon auxiliary roll 24 suitably supported by the elevated frame 25, the sliver, as it passes iii between the draft rolls, being engaged by the lower draft roll and the endless spron 23. Reierring to Fig. 2, the device may be adapted to draw a plurality of strands or groups oi strands of silver through separate sets of iallers, and in this instance the upper draft roll 13 may be provided, as shown in Fig. 2, with a, plurality of endless aprons 223, and may he reduced in diameter between these endless aprons.

In devices having general arrangements as descrioed shove, it has been customary to provide the droit rolls corresponding in position to draft rolls l3 and 1d of the present device with deeply corrugated surfaces so that the upper draft roll, together with an endless epron running there on, would mesh with the lower draft roll and he positively driven thereby. This has necessarily resulted in mutilation oi the endless apron. which runs between the draft rolls. As the endless apron would wear in use it would enter. more deeply into the'oorrugatlons oithe intermeshins draft rolls and as a. consequence cause the silver to follow more nearly the contour of these corrugations. This has resulted'in increasing the rote oi drawing the silver as the endless apron become wormthus altering the ratio or speed of the silver with respect to that oi'the iallers, and therefore. causing uneven drafting of the sliver.

the bite of the rolls, and the To avoid this difficulty, smooth draft rolls might be employed. However, for the upper roll to be driven frictionally by the lower roll, as distinguished from the usual positive drive, such an upper roll, substituted in previous devices, would need to be of large diameter to obtain sufllcient tractive effort from the lower roll to turn against the loading pressure of the springs 28. The use of such an upper roll of large diameter would be inadvisable since it would prevent the fallers from approaching close to the bite of the rollsand hence would allow short fibers to leave the fallers before'being caught by the draft rolls resulting in a. defective product. Furthermore, many existing machines, now equipped with small corrugated rolls, could not have smooth rolls of large diameter substituted therein, because of the structural limitations of the environment of the rolls. I

In the machine of the present invention, these difficulties are avoided by the provision of upper and lower draft rolls 13 and 14 of small diameter so that the fallers 15 may approach close to provision of antifriction bearings for the upper roll 13, so that this roll may readily be frictionally driven regardless of the necessary loading pressure exerted thereon. Such anti-friction bearings are herein illustrated as roller bearings 32 disposed within a suitable race 33 in the upper roll 13. With this improved arrangement of the upper roll, the lower roll 14 may also be substantially a plain cylinder as shown in Fig. 1, instead of corrugated as has been customary. The apron 23 is thus not mutilated in passing between the rolls, is subject to less wear, and does not cause any substantial change in the rate of drafting the sliver upon wearing thin.

The cylindrical surface of the lower or positively driven roll is preferably roughened to an extent which facilitates the traction of the roll with respect to the fibrous strand but not sufficient to cause any substantial mutilation or distortion of the endless apron or equivalent cushioning part. Thus in Fig. 2, the lower roll 14 is shown as provided with narrow flutes 35, which may be for example of the order of 0.1 inch in width and of similar depth, to insure a better grip gilling is not caused to be distorted thereby, as distinguished from the larger corrugations in which the aprons of previous devices were intended to mesh.

In the alternate form of construction of Fig. 4,

the lower or positively driven roll 14 is shown as having its cylindrical surface covered with a hard, granular material 35' such as is commonly used as an abrasive, for example, carborundum. This material likewise aiiords improved frictional contact between the roll 14 and the fibrous strand.

While in the illustrated device the fibrous strand is shown as cushioned by the endless apron 23, it will readily be apparent that for this purpose the apron may in some instances be replaced by a covering of cork, leather, parchment or other somewhat resilient cushioning material fast on the surface of the corresponding draft roll. Either the apron or cushioning surface on the upper'roll, is useful also in providing better frictional engagement with the textile fibers being drafted, thus to prevent slippage of this upper roll with respect to the fibers.

It should be understood that the present disclosure is for the purpose of illustration only and that this invention includes all modifications and equivalents which fall pended claim.

I claim:

'Silver drawing mechanism comprising in combination, upper and lower substantially cylindrical draft rolls of the approximate diameter of the usual small intermeshed or positively geared draft rolls, loading means forcing said rolls together, means in advance of said rolls and located closely adjacent to the nip point, said rolls being free from intermeshing action or positive driving of one by the other, means for driving one of said rolls, and anti-friction bearings for the other of said rolls permitting said latter roll to be driven through the intermediary of the sliver, the mechanism including cushioning means embracing one of the rolls.

within the scope of the ap- EDWARD J. ABBOTT.

Ill 

